Editorial for the Special Issue “Atmospheric Composition and Regional Climate Studies in Bulgaria”

The Special Issue “Atmospheric composition and regional climate studies in Bulgaria” is focused on the following two problems, which are of great societal and scientific importance:

(1) The air has a key effect on the living environment of human beings. A number of atmospheric parameters, such as chemical composition, and physical parameters (e.g., temperature, humidity, wind, and pressure) are of great importance for the quality of life and human health.

(2) Global warming, as strictly defined, is an increase in the global average temperature caused by natural variability or exogenous factors (i.e., the release of greenhouse gases by anthropogenic activities). Global warming is manifested not only by temperature changes but also by changes in the circulation of the ocean–atmosphere system. These changes also lead to changes in the spatial/temporal distribution of precipitation and hence to changes in the global water budgets and changes in the characteristics and spatial/temporal distribution of unfavorable and catastrophic events (drought, storms, hail, floods, fires, sea waves, soil erosion, etc.). The current climate and future climate change will influence ecosystems, all sectors of the economy, and every aspect of human activity as well as quality of life. Global models cannot predict the regional/local characteristics of climate change in detail, so the regional/local-scale specifics of climate change and its consequences have to be taken into account.

This Special Issue aims to promote atmospheric studies in Bulgaria, particularly in the fields of atmospheric composition and climatic research. Bulgaria is a country with complex topography and a variety of ecosystems. There are powerful sources of air pollution in the country, resulting in significant environmental problems not only for the country, but for the neighboring regions of the Balkan Peninsula. On the other hand, knowledge of the atmospheric composition and environmental issues in the country is far from comprehensive. That is why Bulgaria is, by all means, an interesting study object.

This volume includes 11 important articles in the field of scientific and experimental research and numerical modeling related to air quality; the impact of air quality on environment and human health; the origin of air pollution and the processes that form it; current and future regional climates under different global climate change scenarios; regional climate impacts on the environment and quality of life; computer simulation validation and sensitivity studies; studies on interactions of different scales; and evaluations of the effect of resolution on simulated results [1,2,3,4,5,6,7,8,9,10,11].

Therefore, this Special Issue, “Atmospheric composition and regional climate studies in Bulgaria”, has provided a good opportunity for researchers to publish their original research on air pollution and regional climate issues in Bulgaria and to significantly enrich our knowledge on these subjects. Most of the studies also have an applied value, providing scientifically robust information that can be used by local and regional authorities and policy makers as well as by local communities for formulating short-term measures and long-term strategies for dealing with the emerging problems of air quality and climate change.